/*
 * Copyright 2002-2018 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.orm.hibernate5;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.hibernate.FlushMode;
import org.hibernate.HibernateException;
import org.hibernate.JDBCException;
import org.hibernate.NonUniqueObjectException;
import org.hibernate.NonUniqueResultException;
import org.hibernate.ObjectDeletedException;
import org.hibernate.PersistentObjectException;
import org.hibernate.PessimisticLockException;
import org.hibernate.PropertyValueException;
import org.hibernate.QueryException;
import org.hibernate.QueryTimeoutException;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.StaleObjectStateException;
import org.hibernate.StaleStateException;
import org.hibernate.TransientObjectException;
import org.hibernate.UnresolvableObjectException;
import org.hibernate.WrongClassException;
import org.hibernate.cfg.Environment;
import org.hibernate.dialect.lock.OptimisticEntityLockException;
import org.hibernate.dialect.lock.PessimisticEntityLockException;
import org.hibernate.engine.jdbc.connections.spi.ConnectionProvider;
import org.hibernate.engine.spi.SessionFactoryImplementor;
import org.hibernate.exception.ConstraintViolationException;
import org.hibernate.exception.DataException;
import org.hibernate.exception.JDBCConnectionException;
import org.hibernate.exception.LockAcquisitionException;
import org.hibernate.exception.SQLGrammarException;
import org.hibernate.service.UnknownServiceException;
import org.springframework.dao.CannotAcquireLockException;
import org.springframework.dao.DataAccessException;
import org.springframework.dao.DataAccessResourceFailureException;
import org.springframework.dao.DataIntegrityViolationException;
import org.springframework.dao.DuplicateKeyException;
import org.springframework.dao.IncorrectResultSizeDataAccessException;
import org.springframework.dao.InvalidDataAccessApiUsageException;
import org.springframework.dao.InvalidDataAccessResourceUsageException;
import org.springframework.dao.PessimisticLockingFailureException;
import org.springframework.jdbc.datasource.DataSourceUtils;
import org.springframework.lang.Nullable;
import org.springframework.util.Assert;
import org.springframework.util.ClassUtils;
import org.springframework.util.ReflectionUtils;

import javax.persistence.PersistenceException;
import javax.sql.DataSource;
import java.lang.reflect.Method;
import java.util.Map;

/**
 * Helper class featuring methods for Hibernate Session handling.
 * Also provides support for exception translation.
 *
 * <p>Used internally by {@link HibernateTransactionManager}.
 * Can also be used directly in application code.
 *
 * @author Juergen Hoeller
 * @see HibernateExceptionTranslator
 * @see HibernateTransactionManager
 * @since 4.2
 */
public abstract class SessionFactoryUtils
{

    /**
     * Order value for TransactionSynchronization objects that clean up Hibernate Sessions.
     * Returns {@code DataSourceUtils.CONNECTION_SYNCHRONIZATION_ORDER - 100}
     * to execute Session cleanup before JDBC Connection cleanup, if any.
     *
     * @see DataSourceUtils#CONNECTION_SYNCHRONIZATION_ORDER
     */
    public static final int SESSION_SYNCHRONIZATION_ORDER = DataSourceUtils.CONNECTION_SYNCHRONIZATION_ORDER - 100;

    static final Log logger = LogFactory.getLog(SessionFactoryUtils.class);


    private static Method getFlushMode;

    static
    {
        try
        {
            // Hibernate 5.2+ getHibernateFlushMode()
            getFlushMode = Session.class.getMethod("getHibernateFlushMode");
        }
        catch (NoSuchMethodException ex)
        {
            try
            {
                // Hibernate 5.0/5.1 getFlushMode() with FlushMode return type
                getFlushMode = Session.class.getMethod("getFlushMode");
            }
            catch (NoSuchMethodException ex2)
            {
                throw new IllegalStateException("No compatible Hibernate getFlushMode signature found", ex2);
            }
        }
        // Check that it is the Hibernate FlushMode type, not JPA's...
        Assert.state(FlushMode.class == getFlushMode.getReturnType(), "Could not find Hibernate getFlushMode method");
    }


    /**
     * Get the native Hibernate FlushMode, adapting between Hibernate 5.0/5.1 and 5.2+.
     *
     * @param session the Hibernate Session to get the flush mode from
     * @return the FlushMode (never {@code null})
     * @since 4.3
     */
    static FlushMode getFlushMode(Session session)
    {
        FlushMode flushMode = (FlushMode) ReflectionUtils.invokeMethod(getFlushMode, session);
        Assert.state(flushMode != null, "No FlushMode from Session");
        return flushMode;
    }

    /**
     * Trigger a flush on the given Hibernate Session, converting regular
     * {@link HibernateException} instances as well as Hibernate 5.2's
     * {@link PersistenceException} wrappers accordingly.
     *
     * @param session the Hibernate Session to flush
     * @param synch   whether this flush is triggered by transaction synchronization
     * @throws DataAccessException in case of flush failures
     * @since 4.3.2
     */
    static void flush(Session session, boolean synch) throws DataAccessException
    {
        if (synch)
        {
            logger.debug("Flushing Hibernate Session on transaction synchronization");
        }
        else
        {
            logger.debug("Flushing Hibernate Session on explicit request");
        }
        try
        {
            session.flush();
        }
        catch (HibernateException ex)
        {
            throw convertHibernateAccessException(ex);
        }
        catch (PersistenceException ex)
        {
            if (ex.getCause() instanceof HibernateException)
            {
                throw convertHibernateAccessException((HibernateException) ex.getCause());
            }
            throw ex;
        }

    }

    /**
     * Perform actual closing of the Hibernate Session,
     * catching and logging any cleanup exceptions thrown.
     *
     * @param session the Hibernate Session to close (may be {@code null})
     * @see Session#close()
     */
    public static void closeSession(@Nullable Session session)
    {
        if (session != null)
        {
            try
            {
                session.close();
            }
            catch (HibernateException ex)
            {
                logger.debug("Could not close Hibernate Session", ex);
            }
            catch (Throwable ex)
            {
                logger.debug("Unexpected exception on closing Hibernate Session", ex);
            }
        }
    }

    /**
     * Determine the DataSource of the given SessionFactory.
     *
     * @param sessionFactory the SessionFactory to check
     * @return the DataSource, or {@code null} if none found
     * @see ConnectionProvider
     */
    @Nullable
    public static DataSource getDataSource(SessionFactory sessionFactory)
    {
        Method getProperties = ClassUtils.getMethodIfAvailable(sessionFactory.getClass(), "getProperties");
        if (getProperties != null)
        {
            Map<?, ?> props = (Map<?, ?>) ReflectionUtils.invokeMethod(getProperties, sessionFactory);
            if (props != null)
            {
                Object dataSourceValue = props.get(Environment.DATASOURCE);
                if (dataSourceValue instanceof DataSource)
                {
                    return (DataSource) dataSourceValue;
                }
            }
        }
        if (sessionFactory instanceof SessionFactoryImplementor)
        {
            SessionFactoryImplementor sfi = (SessionFactoryImplementor) sessionFactory;
            try
            {
                ConnectionProvider cp = sfi.getServiceRegistry().getService(ConnectionProvider.class);
                if (cp != null)
                {
                    return cp.unwrap(DataSource.class);
                }
            }
            catch (UnknownServiceException ex)
            {
                if (logger.isDebugEnabled())
                {
                    logger.debug("No ConnectionProvider found - cannot determine DataSource for SessionFactory: " + ex);
                }
            }
        }
        return null;
    }

    /**
     * Convert the given HibernateException to an appropriate exception
     * from the {@code org.springframework.dao} hierarchy.
     *
     * @param ex the HibernateException that occurred
     * @return the corresponding DataAccessException instance
     * @see HibernateExceptionTranslator#convertHibernateAccessException
     * @see HibernateTransactionManager#convertHibernateAccessException
     */
    public static DataAccessException convertHibernateAccessException(HibernateException ex)
    {
        if (ex instanceof JDBCConnectionException)
        {
            return new DataAccessResourceFailureException(ex.getMessage(), ex);
        }
        if (ex instanceof SQLGrammarException)
        {
            SQLGrammarException jdbcEx = (SQLGrammarException) ex;
            return new InvalidDataAccessResourceUsageException(ex.getMessage() + "; SQL [" + jdbcEx.getSQL() + "]", ex);
        }
        if (ex instanceof QueryTimeoutException)
        {
            QueryTimeoutException jdbcEx = (QueryTimeoutException) ex;
            return new org.springframework.dao.QueryTimeoutException(ex.getMessage() + "; SQL [" + jdbcEx.getSQL() + "]", ex);
        }
        if (ex instanceof LockAcquisitionException)
        {
            LockAcquisitionException jdbcEx = (LockAcquisitionException) ex;
            return new CannotAcquireLockException(ex.getMessage() + "; SQL [" + jdbcEx.getSQL() + "]", ex);
        }
        if (ex instanceof PessimisticLockException)
        {
            PessimisticLockException jdbcEx = (PessimisticLockException) ex;
            return new PessimisticLockingFailureException(ex.getMessage() + "; SQL [" + jdbcEx.getSQL() + "]", ex);
        }
        if (ex instanceof ConstraintViolationException)
        {
            ConstraintViolationException jdbcEx = (ConstraintViolationException) ex;
            return new DataIntegrityViolationException(ex.getMessage() + "; SQL [" + jdbcEx.getSQL() + "]; constraint [" + jdbcEx.getConstraintName() + "]",
                    ex);
        }
        if (ex instanceof DataException)
        {
            DataException jdbcEx = (DataException) ex;
            return new DataIntegrityViolationException(ex.getMessage() + "; SQL [" + jdbcEx.getSQL() + "]", ex);
        }
        if (ex instanceof JDBCException)
        {
            return new HibernateJdbcException((JDBCException) ex);
        }
        // end of JDBCException (subclass) handling

        if (ex instanceof QueryException)
        {
            return new HibernateQueryException((QueryException) ex);
        }
        if (ex instanceof NonUniqueResultException)
        {
            return new IncorrectResultSizeDataAccessException(ex.getMessage(), 1, ex);
        }
        if (ex instanceof NonUniqueObjectException)
        {
            return new DuplicateKeyException(ex.getMessage(), ex);
        }
        if (ex instanceof PropertyValueException)
        {
            return new DataIntegrityViolationException(ex.getMessage(), ex);
        }
        if (ex instanceof PersistentObjectException)
        {
            return new InvalidDataAccessApiUsageException(ex.getMessage(), ex);
        }
        if (ex instanceof TransientObjectException)
        {
            return new InvalidDataAccessApiUsageException(ex.getMessage(), ex);
        }
        if (ex instanceof ObjectDeletedException)
        {
            return new InvalidDataAccessApiUsageException(ex.getMessage(), ex);
        }
        if (ex instanceof UnresolvableObjectException)
        {
            return new HibernateObjectRetrievalFailureException((UnresolvableObjectException) ex);
        }
        if (ex instanceof WrongClassException)
        {
            return new HibernateObjectRetrievalFailureException((WrongClassException) ex);
        }
        if (ex instanceof StaleObjectStateException)
        {
            return new HibernateOptimisticLockingFailureException((StaleObjectStateException) ex);
        }
        if (ex instanceof StaleStateException)
        {
            return new HibernateOptimisticLockingFailureException((StaleStateException) ex);
        }
        if (ex instanceof OptimisticEntityLockException)
        {
            return new HibernateOptimisticLockingFailureException((OptimisticEntityLockException) ex);
        }
        if (ex instanceof PessimisticEntityLockException)
        {
            if (ex.getCause() instanceof LockAcquisitionException)
            {
                return new CannotAcquireLockException(ex.getMessage(), ex.getCause());
            }
            return new PessimisticLockingFailureException(ex.getMessage(), ex);
        }

        // fallback
        return new HibernateSystemException(ex);
    }

}
